For a padded message, M, using the El Gamal encryption schema, how can we determine the random number $r$, when we are given $p$, the prime number, $g$ which is the primitive root of $p$, $b$ and $x$ ...

I'm reading about the notions of security concerning digital signatures and I can't understand whether RSA is more secure than El Gamal digital signature. Well, they are both prone to forgery, but I ...

What are the properties a generator $g$ should have to be secure for ElGamal signatures (original scheme)?
I am aware that it is poorly chosen and not secure when $g|p-1$ or $g^{-1}|p-1$, where $p$ ...

One difference between RSA and ElGamal is that ElGamal isn't necessarily deterministic (while RSA is).
What makes it non-deterministic? Is this advantageous to security? How else does this property ...

This question is related to ElGamal signature scheme as defined here
ElGamal signature without calculating the inverse
Show how one could exploit an implementation ElGamal signature scheme in which ...